(S05E04) In this episode, Monk must investigate a murder by arson, despite being blinded by the man who committed the crime.

While visiting the local fire station to have his thirty smoke alarms tested, a man from the street walks in. The fire chief tells the man he's not supposed to be there, and then he tries to apprehend him, the man beans the fire chief with a shovel and throws liquid solvent into Monk's eyes, blinding him. The doctor tells Monk it's uncertain whether or not his eyesight will return, and Monk's colleagues do their best to help him out. Disher tries to help out, too, though his idea of helping is to explain everything he's doing, whether it's relevant or not. There's a funny scene later in the episode when Disher is looking for his notebook and tells Monk which pockets he's looking in, as if that even matters. I also laughed when he tells Monk he's going to work 24/7 to figure out who blinded him, except for May 11 because that's when his niece is getting confirmed.